In my experience at least, the olde fears about shortening the life of the chip are non-issue in practice.

I've run overclocked PC's exclusively for about 17 years and never had a single failure, even though I've been running folding@home for most of those. By the time the chip is 4 yrs old it's time for a replacement for practical reasons.

My current system is a cheap Biostar board running a gen-1 i5 750 that I got second hand. The board dates back to 2009 I think. It's overclocked to around 3.6 ghz with turbo still enabled. About time for a replacement but until a year ago it benchmarked at the same level as $200 chips.

Overclocking is definitely still worth it if you want a fast pc for cheap

Not really. As long as you stayed within the thermal envelope, you were fine. I built hundreds of machines from 1995-2005, overclocking most, and I never had a single CPU failure that wasn't just a DOA chip.

Older chips had worse precision and control over overall process (polishing, chemical purity etc). This is a rather niche level knowledge, you would have to ask some ISTFA regular about it.